5 d) - ideal gas molecules Flashcards
What are the gas laws?
- Gas molecules have rapid and random motion.
- When they hit the walls of the container, they exert a force.
- Pressure = Force/Area
What is the absolute zero temperature?
- At absolute zero the particles have no thermal energy or kinetic energy, so they cannot exert a force.
- Absolute zero = 0 Kelvin = -2730C
What is 0 Kelvin into celcius?
-273 C
What does an increase in temperature of a gas?
As you increase the temperature of a gas, the kinetic energy of the gas particles increases and thus their average speed also increases.
What happens when Kelvin temperature increases?
The Kelvin temperature of a gas is proportional to the average kinetic energy of its molecules, so as kelvin temperature increases so does the kinetic energy.
- As you heat the gas, the kinetic energy of the particles increases, and thus so does their average speed.
- This means more collisions per second with the walls, and they exert a larger force on the wall.
- This causes in the total pressure being exerted by the particles to rise.
- If temperature is constant, the average speed of the particles is constant.
- If the same number of particles is placed in a container of smaller volume they will hit the walls of the container more often.
- More collisions per second means that the particles are exerting a larger force on the wall over the same time, so average force exerted on the walls has increased
What is the pressure law?
When volume is constant - for a fixed mass of gas at constant volume, the pressure is directly proportional to the Kelvin temperature
P1/T1 = P2/T2
- The temperature must be in kelvin
What is Boyle’s law?
When temperature is constant - for a fixed mass of gas at constant temperature, the pressure is inversely proportional to the volume.
P1V1 = P2V2
What is charles law?
If the pressure P is constant, then Charles’s law is given by:
V ∝ T
V1/T1 = V2/T2
